To convert torr to centimeters of water, multiply by 1.359509806. That factor is the whole relationship: both units measure pressure, so the conversion is a proportion with no offset and no substance-specific constant.
One millimetre of mercury, used in vacuum work. The unit ventilator and CPAP pressures are set in.
Gauge versus absolute. A tyre gauge reading 32 psi means 32 psi above atmospheric, which is about 46.7 psi absolute. Converting the number is straightforward; remembering which zero it was measured from is where the mistakes happen. N/mm² and MPa are the same size, so a drawing quoting either is quoting the same stress. Two tables follow: rounded steps for quick lookup, and a set of real reference quantities converted into centimeters of water, which is usually more useful than the bare number.
The formula
torr- The amount you are converting, in torr
1.35950980632- The exact number of centimeters of water in one torr
centimeters of water- The converted result
How it works, step by step
- Enter the value in torr.
- It is multiplied by 1.35950980632, the exact factor between the two units.
- The answer is shown in centimeters of water, with the reverse conversion beneath it.
- Check the reference table if you want a figure of comparable size.
Worked examples
A domestic water main: 3000 Torr in centimeters of water
Take a domestic water main, roughly 3000 Torr. The conversion is a single multiplication — 3000 × 1.35951 — giving 4078.53 cmH₂O. Because the relationship is proportional, doubling the input doubles the answer to 8157.06 cmH₂O.
A bicycle tyre: 4650 Torr in centimeters of water
At 4650 Torr (a bicycle tyre), the same quantity in centimeters of water is 4650 × 1.35951 = 6321.72 cmH₂O. One torr is 1.35951 centimeters of water, so the numbers grow as expected.
How to read your score
Frequently asked questions
How many centimeters of water are in one torr?
Exactly 1.35950980632. Every figure on this page is that one number multiplied by your input, so the only rounding is at the display step.
What is the formula to convert torr to centimeters of water?
centimeters of water = torr × 1.35950980632. Reversed, torr = centimeters of water ÷ 1.35950980632, which is the same as multiplying by 0.735559240069.
Which is the bigger unit, the torr or the centimeter of water?
The torr. One torr equals 1.35951 centimeters of water.
What does this quantity actually measure?
Both units measure pressure. That is why a single factor is enough: there is no temperature offset and no material property involved, unlike conversions that cross between different quantities.
What is a torr?
One millimetre of mercury, used in vacuum work.
What is a centimeter of water?
The unit ventilator and CPAP pressures are set in.
Why does my answer differ from another converter?
Almost always because the other tool rounded the factor before multiplying. This page keeps full double precision through the calculation and rounds only for display, and it prints the factor it used so you can see where any difference came from.
Is there a quick way to do Torr to cmH₂O in my head?
Plenty of people do this in their head: multiply by 1.4 instead of using the exact factor 1.359509806. At 100 that shortcut gives 140 centimeters of water, off by 4.049 centimeters of water or about 2.98%. Fine for a rough estimate, not fine for anything you are cutting to size or dosing.
Torr to centimeters of water reference tables
| Torr | Centimeters Of Water |
|---|---|
| 0.5 Torr | 0.679755 cmH₂O |
| 1 Torr | 1.35951 cmH₂O |
| 2 Torr | 2.71902 cmH₂O |
| 3 Torr | 4.07853 cmH₂O |
| 5 Torr | 6.79755 cmH₂O |
| 10 Torr | 13.5951 cmH₂O |
| 20 Torr | 27.1902 cmH₂O |
| 25 Torr | 33.9877 cmH₂O |
| 50 Torr | 67.9755 cmH₂O |
| 75 Torr | 101.963 cmH₂O |
| 100 Torr | 135.951 cmH₂O |
| 250 Torr | 339.877 cmH₂O |
| 500 Torr | 679.755 cmH₂O |
| 1000 Torr | 1359.51 cmH₂O |
| 5000 Torr | 6797.55 cmH₂O |
Exact factor: 1 torr = 1.35950980632 centimeters of water.
| Quantity | Torr | cmH₂O |
|---|---|---|
| Sea-level air | 760 Torr | 1033 cmH₂O |
| A car tyre | 1655 Torr | 2250 cmH₂O |
| Blood pressure, systolic | 120 Torr | 163.1 cmH₂O |
| A bicycle tyre | 4654 Torr | 6328 cmH₂O |
| A domestic water main | 3000 Torr | 4079 cmH₂O |
| A steam boiler | 7501 Torr | 1.02e+04 cmH₂O |
Published reference values, converted with the same factor this page uses.